Social and seasonal variation in dwarf mongoose home-range size, daily movements, and burrow use.

When making decisions about resource use, social species must integrate not only environmental factors but also the influence of opportunities and costs associated with group living. Bigger groups are expected to move further and to need access to larger areas for adequate food acquisition, but the relationships with group size can vary seasonally and with reproductive stage. Shelters are often more consistent in availability than food, but their use relates to factors such as predator defense and parasite transmission that are themselves influenced by group size and seasonality.

Investigating the impact of anthropogenic noise on the decision-making of dwarf mongoose offspring.

Anthropogenic (man-made) noise constitutes a novel and widespread pollutant which is increasing in prevalence in terrestrial and aquatic ecosystems, resulting in alterations of natural soundscapes. There is proliferating evidence that noise leads to maladaptive behaviour in wildlife, yet few studies have addressed the effect on mammalian parent-offspring interactions. We investigated the impact of road noise on dwarf mongoose () offspring nearest-neighbour decision-making while foraging, using a field-based playback experiment.

A positive effect of cumulative intergroup threat on reproductive success.

Outgroup conflict is a powerful selective force across all social taxa. While it is well documented that individual outgroup contests can have a range of direct and indirect fitness consequences, the cumulative pressure of outgroup threats could also potentially impact reproductive success. Here, we use long-term life-history data from a wild population of dwarf mongooses () to investigate how intergroup interaction (IGI) rate might influence breeding and offspring survival.

Behavioural, demographic and fitness consequences of social instability in cooperatively breeding dwarf mongoose groups.

Social instability frequently arises in group-living species, but the potential costs have rarely been investigated in free-living cooperative breeders, especially across different timeframes. Using natural observations, body mass measurements and life-history data from dwarf mongooses (), we determined the short- and long-term consequences of a change in one of the dominant breeding pairs. We found that a new breeder led to alterations in both collective and individual behaviours (i.

Extended and cumulative effects of experimentally induced intergroup conflict in a cooperatively breeding mammal.

Conflict between rival groups is rife in nature. While recent work has begun exploring the behavioural consequences of this intergroup conflict, studies have primarily considered just the 1-2 h immediately after single interactions with rivals or their cues. Using a habituated population of wild dwarf mongooses (), we conducted week-long manipulations to investigate longer-term impacts of intergroup conflict.

Experimental evidence for delayed post-conflict management behaviour in wild dwarf mongooses.

In many species, within-group conflict leads to immediate avoidance of potential aggressors or increases in affiliation, but no studies have investigated delayed post-conflict management behaviour. Here, we experimentally test that possibility using a wild but habituated population of dwarf mongooses (). First, we used natural and playback-simulated foraging displacements to demonstrate that bystanders take notice of the vocalisations produced during such within-group conflict events but that they do not engage in any immediate post-conflict affiliative behaviour with the protagonists or other bystanders.

Animal cooperation: Context-specific helping benefits.

In cooperatively breeding animals, much of the variation in the quantity of help provided by group members remains unexplained. A new study on an Australian songbird suggests we need to look to the context-specific benefits of helping for new insights.

Experimental field evidence that out-group threats influence within-group behavior.

In social species, conspecific outsiders present various threats to groups and their members. These out-group threats are predicted to affect subsequent within-group interactions (e.g.

Experimental evidence for delayed contingent cooperation among wild dwarf mongooses.

Many animals participate in biological markets, with strong evidence existing for immediate cooperative trades. In particular, grooming is often exchanged for itself or other commodities, such as coalitionary support or access to food and mates. More contentious is the possibility that nonhuman animals can rely on memories of recent events, providing contingent cooperation even when there is a temporal delay between two cooperative acts.

Reduced social-information provision by immigrants and use by residents following dispersal.

Greater access to social information is a proposed benefit of group living [1]. However, individuals vary in the quantity and quality of information they provide [2], and prior knowledge about signaller reliability is likely important when receivers decide how to respond [3]. While dispersal causes regular changes in group membership [4], no experimental work has investigated social-information provision and use in this context.

Anthropogenic noise alters dwarf mongoose responses to heterospecific alarm calls.

Anthropogenic noise is an evolutionarily novel and widespread pollutant in both terrestrial and aquatic habitats. Despite increasing evidence that the additional noise generated by human activities can affect vocal communication, the majority of research has focused on the use of conspecific acoustic information, especially sexual signals. Many animals are known to eavesdrop on the alarm calls produced by other species, enhancing their likelihood of avoiding predation, but how this use of heterospecific information is affected by anthropogenic noise has received little empirical attention.

Social-bond strength influences vocally mediated recruitment to mobbing.

Strong social bonds form between individuals in many group-living species, and these relationships can have important fitness benefits. When responding to vocalizations produced by groupmates, receivers are expected to adjust their behaviour depending on the nature of the bond they share with the signaller. Here we investigate whether the strength of the signaller-receiver social bond affects response to calls that attract others to help mob a predator.

Cross-modal impacts of anthropogenic noise on information use.

Anthropogenic noise is a global pollutant, and there is rapidly accumulating evidence of impacts on a range of animal taxa [1,2]. While many studies have considered how additional noise may affect information provision and use, they have focused on the masking and consequent alteration of acoustic signals and cues; so-called unimodal effects [3]. Using field-based experimental trials on habituated wild dwarf mongooses (Helogale parvula) [4], we combine sound playbacks and faecal presentations to demonstrate that anthropogenic noise can disrupt responses to information from different sensory modalities.

Anthropogenic noise disrupts use of vocal information about predation risk.

Anthropogenic noise is rapidly becoming a universal environmental feature. While the impacts of such additional noise on avian sexual signals are well documented, our understanding of its effect in other terrestrial taxa, on other vocalisations, and on receivers is more limited. Little is known, for example, about the influence of anthropogenic noise on responses to vocalisations relating to predation risk, despite the potential fitness consequences.